But a closer read of the FBI’s summary of Tsarnaev’s statements to his interrogators raises questions about key details of the bombing and its execution.

First off, it is important to note that the interview notes are heavily redacted and therefore incomplete. But some of the things the FBI says Dzhokhar told his interrogators indicate a level of confusion or ignorance, or both, about important facts. They also raise questions about why the FBI has been selectively vague about key details of the case.

According to the interrogation notes, “Jahar carried a brown backpack [emphasis added] while his brother’s backpack was black. After parking, they walked…”

Now the backpack is brown?

The indictment, which was written a month and a half after the bombing, states that both bombs were concealed in black backpacks.

In a photograph of the shredded backpack lying in Boylston Street released by the FBI, it does indeed look black...